(a) Field of the Invention
The present invention relates to Micro- or Nano-fluidic chip fabricated with Norland Optical Adhesive (NOA), an acrylated polyurethane-based UV-polymerizable optical adhesive, and bioanalysis platform produced by using the same.
(b) Background Art
A microfluidic chip fabricated by microfluidic technology is a chip containing micro-sized channels. In the microfluidic chip, a small amount of fluid flows through microchannels to make various reactions, which makes it possible to integrate the multiple, complicated laboratory processes on a single chip. Accordingly, it is also called as Lab-on-a-Chip (LOC). As a material for fabricating microchannels, various materials have been studied and used, such as glass, silica, polycarbonate, and poly(methylmethacrylate), poly(dimethylsiloxane) (PDMS). Recently, a nanofluidic chip containing nano-sized channels has been also studied actively, which allows even single molecule detection.
Norland Optical Adhesive (NOA), which is a commercial product developed as an optical adhesive, is a clear, colorless liquid polymer at ambient temperature that will cure when exposed to ultraviolet light. The fully cured NOA is also colorless and clear. Further, the fully cured NOA has an optical properties of a wide spectral range, and mechanical properties of not being easily deformed such as shrinking or expanding due to its hardness. On the basis of those mechanical properties, NOA was suggested as an alternative material in fabricating nanostructures, for substituting the conventional materials such as PDMS.
Capillarity is a phenomenon associated with surface or interfacial tension, and a spontaneous movement of liquids along narrow tubes. PDMS widely used in fabricating microchannels is extremely hydrophobic, in which an extra pumping system is needed in order to flow fluid inside microchannels. However, in the related field, an ideal device is mostly a device having microchannels in which fluid flows by a capillary force without extra external pumping. Accordingly, there are many studies in progress in order to develop such device, and the following methods were reported: a method that PDMS is exposed to energy such as oxygen plasma and UV/ozone to make the surface hydrophilic; a method of further coating with hydrophilic molecules after the above surface treatment; and a method of multiple coating with hydrophilic molecules using sol-gel chemistry.
A microfluidic device is considerably applicable in construction of a bioanalysis platform. A microfluidic chip allows quick immunoassay or DNA even with a very small amount of sample, as well as performing the pretreatment step such as PCR and cell lysis on a single chip. Subsequently, a portable and usable bioanalysis platform has been developed. The bioanalysis platform is expected to play a critical role in realizing POC (point-of-care) of performing diagnostic testing at or near the site of patient care.